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Subscriber Access to Full Article (Nonsubscribers may purchase for $9.00, Includes print PDF, file size: 378159 bytes)
GLOBAL BIOGEOCHEMICAL CYCLES,
VOL. 22,
GB1018,
doi:10.1029/2006GB002854,
2008
Sediment organic carbon burial in agriculturally eutrophic impoundments over the last century
J. A. Downing
Department of Ecology, Evolution, and Organismal Biology, Iowa State University, Ames, Iowa, USA
J. J. Cole
Institute of Ecosystem Studies, Millbrook, New York, USA
J. J. Middelburg
Centre for Estuarine and Marine Ecology, Netherlands Institute of Ecology, Yerseke, Netherlands
R. G. Striegl
United States Geological Survey, Denver, Colorado, USA
C. M. Duarte
Institut Mediterrani d'Estudis Avançats (CSIC-UIB), Esporles, Spain
P. Kortelainen
Finnish Environment Institute, Helsinki, Finland
Y. T. Prairie
Département des Sciences biologiques, Université du Québec à Montréal, Montreal, Quebec, Canada
K. A. Laube
Laube Engineering LLC, Greeley, Colorado, USA
Abstract
We estimated organic carbon (OC) burial over the past century in 40 impoundments in one of the most intensively agricultural
regions of the world. The volume of sediment deposited per unit time varied as a function of lake and watershed size, but
smaller impoundments had greater deposition and accumulation rates per unit area. Annual water storage losses varied from
0.1–20% and were negatively correlated with impoundment size. Estimated sediment OC content was greatest in lakes with low
ratios of watershed to impoundment area. Sediment OC burial rates were higher than those assumed for fertile impoundments
by previous studies and were much higher than those measured in natural lakes. OC burial ranged from a high of 17,000 g C
m−2 a−1 to a low of 148 g C m−2 a−1 and was significantly greater in small impoundments than large ones. The OC buried in these lakes originates in both autochthonous
and allochthonous production. These analyses suggest that OC sequestration in moderate to large impoundments may be double
the rate assumed in previous analyses. Extrapolation suggests that they may bury 4 times as much carbon (C) as the world's
oceans. The world's farm ponds alone may bury more OC than the oceans and 33% as much as the world's rivers deliver to the
sea.
Received 3
October
2006;
accepted 14
September
2007;
published 15
February
2008.
Keywords: agriculture;
burial;
impoundments;
lakes;
organic carbon;
sequestration.
Index Terms: 0428 Biogeosciences: Carbon cycling (4806); 0458 Biogeosciences: Limnology (1845, 4239, 4942); 0496 Biogeosciences: Water quality; 1615 Global Change: Biogeochemical cycles, processes, and modeling (0412, 0414, 0793, 4805, 4912); 1815 Hydrology: Erosion.
Subscriber Access to Full Article (Nonsubscribers may purchase for $9.00, Includes print PDF, file size: 378159 bytes)
Citation: Downing, J. A., J. J. Cole, J. J. Middelburg, R. G. Striegl, C. M. Duarte, P. Kortelainen, Y. T. Prairie, and K. A. Laube
(2008),
Sediment organic carbon burial in agriculturally eutrophic impoundments over the last century,
Global Biogeochem. Cycles,
22,
GB1018,
doi:10.1029/2006GB002854.
Copyright 2008 by the American Geophysical Union.
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